Disintegrating link assembly for cartridge belt



s. s. BRADY 2,970,522 DISINTEGRATING LINK ASSEMBLY FOR CARTRIDGE BELT Feb. 7, 1961 Filed April is, 1959 INVENTOR as. BRAD) ATTORNEY United States Patent DISINTEGRATING LINK ASSEMBLY FOR CARTRIDGE BELT Samuel S. Brady, Baltimore County, Md., assignor to Aircraft Armaments, Inc., Cockeysville, Md., a corporation of Maryland Filed Apr. 16, 1959, Ser. No. 806,898

4 Claims. (Cl. 89--35) This invention relates to disintegrating cartridge belts, and more particularly to link assemblies of the pushthrough type for making up such belts.

Disintegrating cartridge belts are those which utilize the cartridges themselves as hinges or pintles between adjacent link assemblies. The assemblies are so constructed that after the gun loading mechanism strips a cartridge from a link assembly, there is no longer a mechanical connections between it and the remainder of the belt, and the link assembly readily falls away. Certain improved automatic guns employ a loading mechanism having a forward stroke which serves to strip a cartridge from a link assembly and load it into the gun breech. Pushthrough link assemblies are those which provide the requisite clearance for such loading mechanism to act upon a cartridge held in the link assembly.

Link assemblies of the class described may thus comprise a semicylindrical main housing flexibly attached to a semicylindrical attachment link, the parts being in side-by-side relationship with the openings facing in the same direction.

The rear portion of the housing may have an internal diameter which substantially matches the outside di ameter of the rear portion of the cartridge, with the rear portion of the open side being less than the diameter of the cartridge. Thus, the cartridge can be removed from the housing only by being pushed axially through the housing. The forward portion of the housing may be circumferentially enlarged to define with the intermediate portion of the cartridge, an annular recess. The attachment link may have a diameter substantially equal to that of the enlarged portion on the housing and thereby be adapted to nest within the enlarged portion of the housing of an adjacent assembly, and to be rotatable within the annular recess defined by the adjacent housing and cartridge therein. The adjacent cartridge may thus serve to interconnect one link assembly with an adjacent assembly in the same manner that a hinge pintle interconnects two leaves of a hinge.

In order for an automatic firearm utilizing belted ammunition to function properly, it is essential that the belt maintain the pitch distance between adjacent cartridges within the necessary limits as it enters the fire arm. Because the axes of the cartridges are coincident with those of the housing and attachment links, the type of connection between the housing and the attachment link is the factor which controls maintaining pitch, and because the connection permits relative movement of the housing and attachment link, the type of connection is also the factor which controls the degree of flexibility of the belt as a whole. Such connection must therefore prevent the axis of the attachment link from changing its lateral dis lacement from the axis of the housing when the assemblies are adjacent the gun loading mechanism.

In one well known link assembly of the class described, a U-shaped finger on one lateral edge of the attachment link is hooked over an axially arcuate edge 2,970,522 Patented Feb. 7, 1961 portion of the housing to limit relative lateral movement of the axes. An axially extending slot is provided in the edge portion, and a pin engaged in the slot and bridging the U-shaped finger provides the flexible connection between the parts. Thus, when the housing is fixed with its axis in a horizontal plane, the axis of the attachment link is pivotable in a horizontal plane about the center of curvature of the bowed portion on the housing, and is pivotable in a vertical plane about the pin.

While pivotable movement in a. vertical plane is easily accomplished because of the pin-slot connection, pivotable movement in a horizontal plane can occur only as the U-shaped finger slides on the axially arcuate edge portion. Any twisting or cocking of one part with respect to the other in a horizontal plane tends to cause binding of the slideable portions and so restrict pivoting in the horizontal plane. In addition, axial pressure against the cartridge base by the loading mechanism as it strips the cartridge from the assembly tends to cause undesir able pivotal movement of one part with respect to the other because there is nothing on the assembly to retard movement of the pin in the axial slot under these circumstances.

The manufacture of these assemblies presents additional problems when it is considered that the curvature of the finger must be made identical with that of the bowed portion in order to facilitate sliding and to maintain belt pitch. And the fact that a pin must be used further increases the complexity and cost of manufacture.

Much effort has been expended by those skilled in the art to provide a link assembly of the class described which does not require an extra pin to connect the parts of the assembly in order. to achieve belt flexibility, but so far as is known, no successful link assembly of the class described has yet been contributed, and the problems set forth above remain unsolved. It is an object of this invention to provide a link assembly having only two press punched sheet metal parts which may be simply connected to provide for pivotal movement between the parts without allowing any relative sliding while main taining at all times, the correct belt pitch.

As a feature of this invention whereby the objects thereof are achieved, an axially extending flange on one part of the assembly is engaged in an axially extending slot in the other part such that three degrees of freedom of the parts are obtained, With the belt pitch being accurately maintained by decreasing the slot width intermediate the ends of the slot to the thickness of the flange. By this construction, the narrowed part of the slot forms the origin of a coordinate trihedral about whose axes, both parts of the assembly are rotatable, while the ends of the slot limit relative axial movement of the parts.

The more important features of this invention have thus been outlined rather broadly in order that the detailed description thereof that follows may be better un derstood, and in order that the contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will also form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this discolsure is based may readily be utilized as a basis for designing other structures for carrying out the several purposes of this invention. It is important, therefore, that the claims to be granted herein shall be of sufficient breadth to prevent the appropriation of this invention by those skilled in the art.

In the drawings:

Figure 1 is a top view of two link assemblies operatively connected by a cartridge.

' Figure 2 is a side view of a link assembly.

Figure 3 is an end view of the link assembly of Figure 1 showing the manner in which the housing is free to rotate with respect to the attachment link about the connection between the parts.

' Figure 4 is a view similar to Figure 3 but showing how one assembly can rotate with respect to the adjacent assembly about the cartridge therein.

Figure 5 is a view similar to Figure 4 but showing the other extreme of rotation.

Figures 6, 7, 8 and 9 show the manner by which each part of the assembly is allowed to have three degrees of freedom with respect to the other.

Figure 10 is a sectional view illustrating the nesting of the attachment link of one assembly with the enlargement in the housing of an adjacent assembly.

Referring now to Figure 1, reference numerals 10 and 11 designate two link assemblies held together by cartridge 12. Each link assembly comprises a housing 13 and an attachment link 14. Housing 13 is semicylindrical in shape as seen in Figure 3 and has an open side 15. Link 14 is likewise semicylindrical and has an open side 16. The housing and the attachment link are in side-by-side relationship with the openings facing in the same direction. Connector means 17 connects attachment 14 to housing 13.

Opening extends the entire length of housing 13. Rear portion 18 of housing 13 has an internal diameter which substantially matches the outside diameter of the rear portion of cartridge 12. Edges 19 defining the rearward portion of the opening in housing 13 are generally parallel to the axis of the housing, and are spaced apart, a distance less than the diameter of cartridge 12. As a result, the cartridge can be removed from the housing only by pushing the same axially through the housing.

While housing 13 is semicylindrical, insertion of tapered cartridge 12 thereinto causes housing 13 to resiliently deform and frictionally engage the cartridge. In order to properly locate the cartridge in the housing, a spring finger 20 is provided adjacent the rearmost end of the housing with a detent portion 21 engageable with the extraction groove in the cartridge. With this arrangement, the gun loading mechanism is able to engage the rear of cartridge 12 and by pushing thereagainst, strip the cartridge from the housing since detent 21 is cammed out of the extraction groove by the rim. Thus, the detent construction allows the gun loading mechanism to push the round through the housing while properly maintaining the cartridge position. However, it is usually necessary to insure that the round does not back out of the housing during handling of belted ammunition. This is accomplished by notching the housing diametrically opposite to detent 21 and bending the end thereof into the extractor groove as indicated at 22. As seen in Figure 1, the rim will cam end 22 out of the way as the cartridge is pushed through the housing by the gun loading mechanism. However, bend 22 will engage the extractor groove upon initial rearward movementrnent of the cartridge through the housing and prevent further rearward movement. By such arrangement, cartridge 12 may be inserted nose first through the rear of housing 13, with the sides of the cartridge camming detent 21 and bend 22 out of the way until they snap into the extractor groove and securely position the cartridge in the housing.

The forward portion of housing 13 is enlarged at 23. Enlargement 23 extends circumferentially around the housing and is of a diameter in excess of the diameter of the intermediate portion of cartridge 12 as shown in Figure 2. Thus, enlargement 23 defines, with the intermediate portion of cartridge 12, an annular recess. Notch 24 is provided in one side edge of enlargement 23. The interior edge of notch 24 is rounded and extends beyond the projection of the centerline on enlargement 23. The side edge opposite and forward of notch 24 is relieved as shown at 25. The purpose of notch 24 and relieved portion 25 will become apparent hereinafter.

Attachment link 14 may have a diameter substantially equal to that of enlargement 23 on housing 13. By this arrangement, the attachment link on one assembly can be nested within the enlarged portion of the housing of an adjacent assembly as shown in Figure 10. The annular recess between enlargement 23 and cartridge 12 allows link 14 to be rotatable around the cartridge as shown in Figure 4 and Figure 5.

Link 14 may advantageously be made with a taper, as best seen in Figure 10, which matches the taper of cartridge 12. The forward portion of link 14 may have lip 26 thereon so that the dimension from the axis of the link to the lip is the same as that from the axis to the rearmost edge. By this arrangement, the rearmost edge of link 14 is engaged in the rear portion of enlargement 23 and lip 26 is engaged in the forward portion of enlargement 23 and the axis of the link is coincident with the axis of the housing. Rotation of link 14 with respect to cartridge 12 and enlargement 23 is readily accomplished because the internal dimensions of link 14 slightly exceed the external dimensions of cartridge 12, while the external dimension of link 14 is slightly less than the internal diameter of enlargement 23. When attachment link 14 of one assembly is thus nested in enlargement 23 of an adjacent housing, insertion of cartridge 12 into the housing will interconnect the assemblies in the same manner that a hinge pintle interconnects two leaves of a hinge.

Connector means 17 includes flange 27 on housing 13 and flange 28 on attachment link 14. When housing 13 and link 14 are in side-by-side relationship with openings 15, 16 facing in the same direction, and the axes of housing 13 and link 14 defining a plane, base portion 29 of flange 27 is outwardly directed from housing 13 substantially parallel to the plane. As seen in Figures 1, 6 and 7, flange 27 is axially extending in that its major dimension is parallel to the axes. Intermediate portion 30 of flange 27 is directed normal to the plane as is seen in Figure 8. Terminal portion 31 is outwardly directed from housing 13 and is substantially parallel to the plane. Flange 28 is outwardly directed from link 14 in a plane parallel to the plane defined by the axes. Flange 28 is provided with an axially extending aperture 32 in which intermediate portion 30 is engaged.

Aperture 32 is shaped like a figure-eight having wider dimensions at either of its axial ends than at its center. Protuberances 33 at the center of aperture 32 narrow the dimension at the center to substantially the thickness of intermediate portion 30 as seen in Figures 6 and 7. The length of intermediate portion 30 is slightly greater than the thickness of flange 28 as seen in Figure 8.

It will be evident to those skilled in the art that each part of a link assembly can be punched from sheet metal and properly formed with portions 30 and 31 being aligned. Connection of the parts is achieved by insertion of portions 30 and 31 into slot 32 followed by bending portion 31 normal to portion 30.

Connection 17 thus forms a means by which housing 13 and attachment link 14 may partake of universal movement. The broken line showings of housing 13 in Figures 1, 2 and 3 indicate the manner in which the housing is movable relative to the attachment link (or the attachment link is movable relative to the housing) about the axes of a coordinate trihedral whose origin is between protuberances 33. As shown in Figure 1, the link assernbly on the right is initially positioned with the axis of the housing parallel with that of the attachment link to define a reference plane which may be considered as being horizontal. Intermediate portion 30 is axially di rected as shown in Figure 6 and is parallel to the axis of the attachment link. Because aperture 32 has wider dimensions at either of its axial ends, housing 14 may pivot about protuberances 33 in either direction (as 'shown in Figure 7), while the axis of the housing remains horizontal. The limits of rotation about a vertical axis passing intermediate protuberances 33 are gov erned by engagement of relieved portion 25 on one housing with enlargement 23 on an adjacent housing, and by engagement of the rear portions of the housings.

With the axes again horizontal, base portion 29 engages flange 28 as shown in solid lines in Figure 9. From this position, housing 13 may be rotated to raise either the forward or the rearward end of the housing to cause the axis of the housing to rotate in a vertical plane. The limits of rotation about a horizontal axis passing substantially intermediate the thickness of flange 28 are determined by the engagement of intermediate portion 30 with the walls defining aperture 32 as best shown in Figure 9. It should be noted that intermediate portion 30 is slightly longer than the thickness of flange 28 to allow for this movement.

This same feature also allows housing 13 to partake of rotation about link 14 as shown by the broken lines in Figures 3 and 8. Thus, with both axes horizontal housing 13 is rotatable about a horizontal axis parallel to those of the housing and attachment link which passes :substantially intermediate the thickness of flange 28. It is thus apparent that when attachment link 14 is held fixed, housing 13 can rotate freely about a point between protuberances 33 with three degrees of freedom.

With cartridge 12 serving as connector between adjacent links, attachment link 14 is rotatable in the annular recess of an adjacent housing in a conventional manner :as illustrated by Figures 4 and 5. Notch 24 provides clearance for connector means 17 as one assembly rotates about the cartridge.

It should be noted that the great amount of freedom permitted by connector means 17 between link assemblies .allows the belt as a whole to be extremely flexible. Yet belt pitch is absolutely maintained by protuberances 33. In addition, axial movement of the housing with respect to the attachment link is limited by the forward and rearwardlimits of aperture 32. Thus, axial thrust on a cartridge is taken, after limited movement, by the walls of aperture 32 without any pivoting.

Those skilled in the art will now appreciate that by the present invention there is contributed a push-through link assembly for a disintegrating cartridge belt which has only two parts, each of which may be fashioned from sheet metal. the parts allows them to have three degrees of freedom without any sliding engagement while the pitch between cartridges is positively maintained. By providing three degrees of freedom between the parts of the link assembly, the cartridge belt may be stored in a drum by helically winding the belt about a core. The relieved portion on the housings permits maximum helical twisting of the assembly while the simple connection between the parts of the assembly permits the belt to be fed easily along a helical path with a minimum of resistance.

What is claimed is:

1. A cartridge belt link assembly adapted to cooperate with other similar links for forming a disintegrating cartridge belt comprising, a generally semicylindrical housing having an open side, a generally semicylindrical attachment link having an open side, said housing and attachment link being in side-by-side relationship with the openings facing in the same direction, and connector means connecting said attachment to said housing, said connector means including an axially extending first flange on said housing having an outwardly directed first portion parallel to the plane defined by the axes of the housing and attachment link, a second portion directed normal to the plane and an outwardly directed third portion parallel to the plane, and an axially extending outwardly directed second flange on said attachment link parallel to the plane, said second flange having an axially extending slot in which said second por- Furthermore, a simple connection between,

6 tion of the first flange is engaged, said slot being wide'r at its axial ends than at its center, the width of the slot at its center being substantially equal to the thickness of said second portion so that said housing is pivotal with respect to said attachment about each axis of a coordinate trihedral whose origin is intermediate the center of said slot, the engagement of said second portion of said first flange in said axial slot constituting the sole connection between the housing and the attachment link.

2. A cartridge belt link assembly adapted to cooperate with other similar links for forming a disintegrating cartridge belt comprising, a generally semicylindrical housing adapted to slideably receive a cartridge, said housing having an opening extending the length thereof, the rearward portion of said housing having longitudinal edges with the spacing therebetween being less than the diameter of said housing, the forward portion of said housing having an enlargement extending circumferentially therearound for defining an annular recess with the cartridge, a tab on the enlargement having an intermediate part outwardly spaced from the enlargement and extending substantially normal to the plane defined by said edges and having a terminal part directed away from the enlargement and extending substantially perpendicular to said intermediate part, a generally semicylindrical attachment link adapted to engage a cartridge and having an opening extending the length thereof, an outwardly directed flange on said attachment link having a longitudinally extending aperture therein in which said intermediate part is engaged, the aperture being generally wider than the thickness and longer than the length of said intermediate part, and opposite protuberances on the longitudinal sides of the aperture intermediate the ends thereof locally decreasing its width to a dimension substantially the same as the thickness of said intermediate part, said attachment link being of a diameter to slideably fit within the annular recess on an adjacent link assembly, the engagement of said intermediate part in said aperture constituting the only connection between said housing and said attachment link, said terminal part serving to prevent separation of the housing from the attachment link.

3. A cartridge belt link assembly adapted to cooperate with other similar links for forming a disintegrating cartridge belt comprising: a generally semicylindrical housing having an open side; a generally semicylindrical attachment link having an open side, said housing and attachment link being a side-by-side relationship with the openings facing in the same direction; and connector means connecting said attachment link to said housing so that when the housing and attachment link are in a normal position, the axes of said housing and attachment link are parallel and define a plane, said connector means including: a first flange on said housing having a first portion directed outwardly from the housing parallel to said plane when the housing and attachment link are in normal position, said first flange having an intermediate portion directed normal to said first portion and having a terminal portion directed parallel to said first portion; and a second flange on said attachment link directed outwardly therefrom parallel to said plane when the housing and link are in normal position, said second flange having an axial slot therein in which said intermediate portion of said first flange is engaged, said second flange being engaged between the first and terminal portions of said first flange, said slot being wider at its axial ends than at its center, the width of the slot at its center being substantially equal to the thickness of said intermediate portion so that said housing and attachment link are relatively movable from their normal position, said terminal portion on said first flange serving to prevent separation of the housing and attachment link.

4. A cartridge belt link assembly adapted to cooperate with other similar links for forming a disintegrating cartridge belt comprising: two generally semicylindrical members having open sides, the normal position of said members being side-by-side with the openings facing in the same direction and the axes of the members defining a plane; and connector means connecting said members together to effect relative movement therebetween, said connector means including: a flange on one member having a first portion directed outwardly from said one member parallel to said plane when the members are in normal position, said flange having an intermediate portion that is normal to said first portion and a terminal portion that is parallel to said first portion, said terminal portion being directed outwardly from said one member; and a flange on the other member directed outwardly therefrom parallel to said plane when the members are in normal position, said last mentioned flange having an 1 axial slot therein in which the intermediate portion of the first mentioned flange is engaged, said last mentioned flange being engaged between and in contact with the first and terminal portions of said first mentioned flange when the members are in normal position for preventing separation of the members and limiting relative movement between the members, said slot being wider at its axial ends than at its center, the width of the slot at its center being substantially equal to the thickness of said intermediate portion so that said members are relatively movable about each axis of a coordinate trihedral whose origin is intermediate the center of said slot.

References Cited in the file of this patent UNITED STATES PATENTS 2,480,972 Sanford et al. Sept. 6, 1949 

